Pub Date : 2023-11-06DOI: 10.24425/cpe.2019.130212
Zuzanna Bojarska, M. Mazurkiewicz-Pawlicka, Ł. Makowski
The aim of the presented research was to test different carbon supports, such as graphene oxide (GO), graphene oxide modified with ammonia (N-GO), and reduced graphene oxide (rGO) for catalysts used in a low-temperature fuel cell, specifically a proton exchange membrane fuel cell (PEMFC). Modification of the carbon supports should lead to different catalytic activity in the fuel cell. Reduction of GO leads to partial removal of oxygen groups from GO, forming rGO. Modification of GO with ammonia results in an enrichment of GO structure with nitrogen. A thorough analysis of the used supports was carried out, using various analytical techniques, such as FTIR spectroscopy and thermogravimetric (TGA) analysis. Palladium and platinum catalysts deposited on these supports were produced and used for the oxygen reduction reaction (ORR). Catalytic activity tests of the prepared catalysts were carried out in a home-made direct formic acid fuel cell (DFAFC). The tests showed that the enrichment of the GO structure with nitrogen caused an increase in the catalytic activity, especially for the palladium catalyst. However, reduction of GO resulted in catalysts with higher activity and the highest catalytic activity was demonstrated by Pt/rGO, because platinum is the most catalytically active metal for ORR. The obtained results may be significant for low-temperature fuel cell technology, because they show that a simple modification of a carbon support may lead to a significant increase of the catalyst activity. This could be useful especially in lowering the cost of fuel cells, which is an important factor, because thousands of fuel cells running on hydrogen are already in use in commercial vehicles, forklifts, and backup power units worldwide. Another method used for lowering the price of current fuel cells can involve developing new clean and cheap production methods of the fuel, i.e. hydrogen. One of them employs catalytic processes, where carbon materials can be also used as a support and it is necessary to know how they can influence catalytic activity.
{"title":"Graphene oxide-based nano-materials as catalysts for oxygen reduction reaction","authors":"Zuzanna Bojarska, M. Mazurkiewicz-Pawlicka, Ł. Makowski","doi":"10.24425/cpe.2019.130212","DOIUrl":"https://doi.org/10.24425/cpe.2019.130212","url":null,"abstract":"The aim of the presented research was to test different carbon supports, such as graphene oxide (GO), graphene oxide modified with ammonia (N-GO), and reduced graphene oxide (rGO) for catalysts used in a low-temperature fuel cell, specifically a proton exchange membrane fuel cell (PEMFC). Modification of the carbon supports should lead to different catalytic activity in the fuel cell. Reduction of GO leads to partial removal of oxygen groups from GO, forming rGO. Modification of GO with ammonia results in an enrichment of GO structure with nitrogen. A thorough analysis of the used supports was carried out, using various analytical techniques, such as FTIR spectroscopy and thermogravimetric (TGA) analysis. Palladium and platinum catalysts deposited on these supports were produced and used for the oxygen reduction reaction (ORR). Catalytic activity tests of the prepared catalysts were carried out in a home-made direct formic acid fuel cell (DFAFC). The tests showed that the enrichment of the GO structure with nitrogen caused an increase in the catalytic activity, especially for the palladium catalyst. However, reduction of GO resulted in catalysts with higher activity and the highest catalytic activity was demonstrated by Pt/rGO, because platinum is the most catalytically active metal for ORR. The obtained results may be significant for low-temperature fuel cell technology, because they show that a simple modification of a carbon support may lead to a significant increase of the catalyst activity. This could be useful especially in lowering the cost of fuel cells, which is an important factor, because thousands of fuel cells running on hydrogen are already in use in commercial vehicles, forklifts, and backup power units worldwide. Another method used for lowering the price of current fuel cells can involve developing new clean and cheap production methods of the fuel, i.e. hydrogen. One of them employs catalytic processes, where carbon materials can be also used as a support and it is necessary to know how they can influence catalytic activity.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68947380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/CPE.2019.130218
E. Molga
{"title":"Editor’s notes. In memoriam of Professor Wioletta Podgórska","authors":"E. Molga","doi":"10.24425/CPE.2019.130218","DOIUrl":"https://doi.org/10.24425/CPE.2019.130218","url":null,"abstract":"","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68947521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/CPE.2019.130224
K. Ulatowski, J. Fiuk, P. Sobieszuk
In this paper, three methods of sterilisation are compared to determine their usability in nanobubble dispersion sterilisation: filtration, thermal sterilisation and sonication (in two systems: using a sonotrode and sonication bath). Nanobubble dispersions are most commonly generated in non-sterile systems which precludes them from use in most biological research. As a result of this study, filtration was chosen as the best method for nanobubble sterilisation.
{"title":"Sterilisation of nanobubble dispersions","authors":"K. Ulatowski, J. Fiuk, P. Sobieszuk","doi":"10.24425/CPE.2019.130224","DOIUrl":"https://doi.org/10.24425/CPE.2019.130224","url":null,"abstract":"In this paper, three methods of sterilisation are compared to determine their usability in nanobubble dispersion sterilisation: filtration, thermal sterilisation and sonication (in two systems: using a sonotrode and sonication bath). Nanobubble dispersions are most commonly generated in non-sterile systems which precludes them from use in most biological research. As a result of this study, filtration was chosen as the best method for nanobubble sterilisation.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"41 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68947669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2018.124993
The quantitative description of an airlift bioreactor, in which aerobic biodegradation limited by car-bonaceoussubstrate and oxygendissolved in a liquid takes place, is presented. This process is described by the double-substrate kinetics. Mathematical models based on the assumption of plug flow and dispersion flow of liquid through the riser and the downcomer in the reactor were proposed. Calculations were performed for two representative hydrodynamic regimes of reactor operation, i.e. with the presence of gas bubbles only within the riser and for complete gas circulation. The analysis aimed at how the choice of a mathematical model of the process would enable detecting the theoretical occurrence of oxygen deficiency in the airlift reactor. It was demonstrated that the simplification of numerical calculations by assuming the “plug flow” model instead of dispersion with high Péclet numbers posed a risk of improper evaluation of the presence of oxygen deficiency zones. Conclusions related to apparatus modelling and process design were drawn on the basis of the results obtained. The paper is a continuation of an earlier publication (Grzywacz, 2012a) where an analysis of single-substrate models of the airlift reactor was presented.
{"title":"Models of airlift bioreactors for double-substrate kinetics. The analysis of sufficient oxygenation conditions with a view of mathematical model choice","authors":"","doi":"10.24425/cpe.2018.124993","DOIUrl":"https://doi.org/10.24425/cpe.2018.124993","url":null,"abstract":"The quantitative description of an airlift bioreactor, in which aerobic biodegradation limited by car-bonaceoussubstrate and oxygendissolved in a liquid takes place, is presented. This process is described by the double-substrate kinetics. Mathematical models based on the assumption of plug flow and dispersion flow of liquid through the riser and the downcomer in the reactor were proposed. Calculations were performed for two representative hydrodynamic regimes of reactor operation, i.e. with the presence of gas bubbles only within the riser and for complete gas circulation. The analysis aimed at how the choice of a mathematical model of the process would enable detecting the theoretical occurrence of oxygen deficiency in the airlift reactor. It was demonstrated that the simplification of numerical calculations by assuming the “plug flow” model instead of dispersion with high Péclet numbers posed a risk of improper evaluation of the presence of oxygen deficiency zones. Conclusions related to apparatus modelling and process design were drawn on the basis of the results obtained. The paper is a continuation of an earlier publication (Grzywacz, 2012a) where an analysis of single-substrate models of the airlift reactor was presented.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"1 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135635066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2021.137341
{"title":"Professor Jerzy Bałdyga – Personal memories","authors":"","doi":"10.24425/cpe.2021.137341","DOIUrl":"https://doi.org/10.24425/cpe.2021.137341","url":null,"abstract":"","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"22 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135635080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2021.137337
A series of steps taken to determine a kinetic equation that describes hydrogenation of propene on nickel catalyst is presented in this study. Mixed factorial design approach, belongs to designing of experiments methods was used to plane experiments. The investigations showed that the method applied makes possible determination of the kinetic equation in a relatively fast and cheap manner since only a few measurement points is required. The equation obtained was verified experimentally and statistically. Both tests showed satisfactory precision of anticipated values of the process rate.
{"title":"Kinetic investigations of heterogeneous reactor processes – Optimization of experiments","authors":"","doi":"10.24425/cpe.2021.137337","DOIUrl":"https://doi.org/10.24425/cpe.2021.137337","url":null,"abstract":"A series of steps taken to determine a kinetic equation that describes hydrogenation of propene on nickel catalyst is presented in this study. Mixed factorial design approach, belongs to designing of experiments methods was used to plane experiments. The investigations showed that the method applied makes possible determination of the kinetic equation in a relatively fast and cheap manner since only a few measurement points is required. The equation obtained was verified experimentally and statistically. Both tests showed satisfactory precision of anticipated values of the process rate.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"389 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2019.130210
Nesa Dibagar, Stefan Jan Kowalski, Reza Amiri Chayjan
Evaluation of moisture absorption in foodstuffs such as black chickpea is an important stage for skinning and cropping practices. Water uptake process of black chickpea was discussed through normal soaking in four temperature levels of 20, 35, 50 and 65 ◦ C for 18 hours, and then the hydration kinetics was predicted by Peleg’s model and finite difference strategy. Model results showed that with increasing soaking temperature from 20 to 65 ◦ C, Peleg’s rate and Peleg’s capacity constant reduced from 13 : 368 (cid:2) 10 (cid:0) 2 to 5 : 664 (cid:2) 10 (cid:0) 2 and 9 : 231 (cid:2) 10 (cid:0) 3 to 9 : 138 (cid:2) 10 (cid:0) 3 , respectively. Based on key results, a rise in the medium temperature caused an increase in the diffusion coefficient from 5 : 24 (cid:2) 10 (cid:0) 10 m 2 /s to 4 : 36 (cid:2) 10 (cid:0) 9 m 2 /s, as well. Modelling of moisture absorption of black chickpea was also performed employing finite difference strategy. Comparing the experimental results with those obtained from the analytical solution of the theoretical models revealed a good agreement between predicted and experimental data. Peleg’s model and finite difference technique revealed their predictive function the best at the temperature of 65 ◦ C.
{"title":"Water absorption of black chickpea using a finite difference method","authors":"Nesa Dibagar, Stefan Jan Kowalski, Reza Amiri Chayjan","doi":"10.24425/cpe.2019.130210","DOIUrl":"https://doi.org/10.24425/cpe.2019.130210","url":null,"abstract":"Evaluation of moisture absorption in foodstuffs such as black chickpea is an important stage for skinning and cropping practices. Water uptake process of black chickpea was discussed through normal soaking in four temperature levels of 20, 35, 50 and 65 ◦ C for 18 hours, and then the hydration kinetics was predicted by Peleg’s model and finite difference strategy. Model results showed that with increasing soaking temperature from 20 to 65 ◦ C, Peleg’s rate and Peleg’s capacity constant reduced from 13 : 368 (cid:2) 10 (cid:0) 2 to 5 : 664 (cid:2) 10 (cid:0) 2 and 9 : 231 (cid:2) 10 (cid:0) 3 to 9 : 138 (cid:2) 10 (cid:0) 3 , respectively. Based on key results, a rise in the medium temperature caused an increase in the diffusion coefficient from 5 : 24 (cid:2) 10 (cid:0) 10 m 2 /s to 4 : 36 (cid:2) 10 (cid:0) 9 m 2 /s, as well. Modelling of moisture absorption of black chickpea was also performed employing finite difference strategy. Comparing the experimental results with those obtained from the analytical solution of the theoretical models revealed a good agreement between predicted and experimental data. Peleg’s model and finite difference technique revealed their predictive function the best at the temperature of 65 ◦ C.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"286 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135678904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2019.126107
The study concerns modeling and simulation of the growth of biofilms with heterogeneous structures with a discrete mathematical model based on theory of cellular automata. The article presents two-dimensional density distributions of biofilms for microbial processes: oxidation of ammonium by Nitrosomonas europaea bacteria and glucose utilization by Pseudomonas aeruginosa bacteria. The influence of limiting substrate concentration in the liquid phase on biofilm structure was determined. It has been shown that the value of death rate coefficient of microorganisms has the qualitative and quantitative influence on the density and porosity of the biofilm.
{"title":"Cellular-automata based modeling of heterogeneous biofilm growth for microbiological processes with various kinetic models","authors":"","doi":"10.24425/cpe.2019.126107","DOIUrl":"https://doi.org/10.24425/cpe.2019.126107","url":null,"abstract":"The study concerns modeling and simulation of the growth of biofilms with heterogeneous structures with a discrete mathematical model based on theory of cellular automata. The article presents two-dimensional density distributions of biofilms for microbial processes: oxidation of ammonium by Nitrosomonas europaea bacteria and glucose utilization by Pseudomonas aeruginosa bacteria. The influence of limiting substrate concentration in the liquid phase on biofilm structure was determined. It has been shown that the value of death rate coefficient of microorganisms has the qualitative and quantitative influence on the density and porosity of the biofilm.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"279 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135678913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2021.138934
The paper presents a research work on the process of emulsion separation by filtration-coalescence method in the presence of solid particles. A polyester PBT coalescence medium was used in experiments of water removal from diesel fuel. Apart from parameters representing the geometry and inherent properties of coalescence filters, the additional emulsion constituents such as surfactants and solid particles also affect the process. These constituent can cover fibres and they can also influence emulsion properties. It has been experimentally confirmed that contrary to surface active compounds, which stabilise the emulsion, the presence of specific solid particles decreased the system stability. If surface active compounds are present in the system, the influence of solid particles is different at the same concentration level depending on their type. The destabilization of emulsion due to the presence of Arizona dust was more pronounced. Although the presence of particles mitigated the effect of surfactants, their deposition in the filter media oppositely affected the coalescence process depending on solid type. Oleophilic iron oxide particles improved the separation efficiency of water from diesel fuel, while Arizona test dust had a negative impact on the separation process performance.
{"title":"The effect of solids on interfacial rheology and the performance of coalescence filters","authors":"","doi":"10.24425/cpe.2021.138934","DOIUrl":"https://doi.org/10.24425/cpe.2021.138934","url":null,"abstract":"The paper presents a research work on the process of emulsion separation by filtration-coalescence method in the presence of solid particles. A polyester PBT coalescence medium was used in experiments of water removal from diesel fuel. Apart from parameters representing the geometry and inherent properties of coalescence filters, the additional emulsion constituents such as surfactants and solid particles also affect the process. These constituent can cover fibres and they can also influence emulsion properties. It has been experimentally confirmed that contrary to surface active compounds, which stabilise the emulsion, the presence of specific solid particles decreased the system stability. If surface active compounds are present in the system, the influence of solid particles is different at the same concentration level depending on their type. The destabilization of emulsion due to the presence of Arizona dust was more pronounced. Although the presence of particles mitigated the effect of surfactants, their deposition in the filter media oppositely affected the coalescence process depending on solid type. Oleophilic iron oxide particles improved the separation efficiency of water from diesel fuel, while Arizona test dust had a negative impact on the separation process performance.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"276 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135678918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/cpe.2021.138921
Efficiency of agitation was considered for different physical systems on the basis of our own experimental studies on homogenisation, heat and mass transfer as well as gas hold-up. Measurements were performed for different physical systems: Newtonian liquids of low and higher viscosity, pseudoplas-tic liquid, gas–liquid and gas–solid–liquid systems agitated in vessels of the working volume from 0.02 m 3 to 0.2 m 3 . Agitated vessels of different design were equipped with a high-speed impeller (10 impellers were tested). Comparative analysis of the experimental results proved that energy inputs (power consumption) should be taken into account as a very important factor when agitation efficiency is evaluated in order to select a proper type of equipment. When this factor is neglected in the analysis, intensification of the process can be estimated only.
{"title":"Agitation efficiency of different physical systems","authors":"","doi":"10.24425/cpe.2021.138921","DOIUrl":"https://doi.org/10.24425/cpe.2021.138921","url":null,"abstract":"Efficiency of agitation was considered for different physical systems on the basis of our own experimental studies on homogenisation, heat and mass transfer as well as gas hold-up. Measurements were performed for different physical systems: Newtonian liquids of low and higher viscosity, pseudoplas-tic liquid, gas–liquid and gas–solid–liquid systems agitated in vessels of the working volume from 0.02 m 3 to 0.2 m 3 . Agitated vessels of different design were equipped with a high-speed impeller (10 impellers were tested). Comparative analysis of the experimental results proved that energy inputs (power consumption) should be taken into account as a very important factor when agitation efficiency is evaluated in order to select a proper type of equipment. When this factor is neglected in the analysis, intensification of the process can be estimated only.","PeriodicalId":55267,"journal":{"name":"Chemical and Process Engineering-Inzynieria Chemiczna I Procesowa","volume":"315 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135679068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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